Big-Block Cylinder Heads - Head Trip, Part 2

Big-block heads for the spendthrift builder

Oxymoron. Webster's dictionary defines this word as: "a combination of contradictory or incongruous words (as cruel kindness); broadly: something (as a concept) that is made up of contradictory or incongruous elements."

Besides "cruel kindness" here are some other examples: adult male, authentic replica, honest politician, jumbo shrimp, and military intelligence. For a long time, people would put the phrase "budget big-block" in there, too. But a little research proved there are very good values out there for those building a Rat with an eye on cost conservation.

In the last issue of Super Chevy, we went down the list of cylinder head manufacturers and got the latest dope from each company on their most popular off-the-shelf small-block cylinder heads. Mind you, we also informed each company that our aim was to search out their best "cost-conscious" cylinder heads. This month, we searched out those same parts for Chevy's fabled Rat motor. Yes, it's true that when one dives into the big-block waters, budget is a word that seldom comes to mind. Budgets, however, are like waist sizes-they vary from person to person. If only our wallets were akin to our waist sizes, what a wonderful world this would be.

It turns out that purchasing a set of BBC cylinder heads won't require you to sell a kidney on the black market; they're more affordable than you may think. When purchasing a set of cylinder heads, most DIYers prefer the out-of-the-box, preassembled units. Unless you're running some insanely wild cam, the springs and valves in the preassembled heads are capable of delivering some great performance numbers over the OE-spec heads. In no particular order, here are the companies we contacted and the information they provided.

World has a couple of BB heads that are perfect for the budget builder. The first one is the assembled Merlin oval port cast iron head, with a 269cc intake volume, a 119cc combustion chamber, 2.300x1.88 valves and 11/32 guides. Out of the box these heads run about $720. The next step up is the Merlin III. This head features a 320cc intake chamber and opens up to a 345cc intake chamber. The combustion chamber, valves and guides are the same as the Merlin. An assembled set of the 345cc heads will run about $1,459.

4/17

Racing Head Service(877) 766-4323www.racingheadservice.com

Pro Action Cast Iron 320cc Cylinder Head, 360cc BBC Cylinder Head

Racing Head Service knocked one out with its Pro Action cast iron heads. The Pro Action heads come in a 320cc and 360cc intake runner. Both heads feature a 119cc combustion chamber with intake valves (with hardened seats) that measure 2.250 and exhaust valves that measure 1.880. A pair of assembled 360cc heads built for a hydraulic roller cam runs about $1,810. The same set built for a mechanical roller runs about $2,064.

5/17

Summit Racing Equipment(800) 230-3030www.summitracing.com

Square Port Iron 308cc BBC Cylinder Head

Millions have ordered parts from Summit Racing, but some may not be familiar with the fact that Summit also offers its own line of cylinder heads for the Chevy big-block. Summit has set of cast-iron heads that are ready to run from the moment you open the box. The Summit square port iron heads feature a 308cc intake runner with a 119cc combustion chamber, a 2.250 intake valve and a 1.880 exhaust valve with hardened seats. A pair of assembled heads runs about $1,291.

6/17

Brodix(479) 394-1075www.brodix.com

Race Rite BB-R 294cc, BB-O 270cc BBC Cylinder Head

Brodix has a direct replacement for stock cast-iron heads. These heads from its Race Rite series are made from cast aluminum and are available in rectangular or oval port castings. Brodix has also designed the Race Rite heads to work directly with the stock pistons and intake manifold. The Race Rite heads come in two available sizes: the BB-R comes with a 294cc intake port while the BB-O comes with a 270cc intake port. Both heads have a 119cc combustion chamber, a 2.250 intake valve, and a 1.880 exhaust valve. An out-of-the-box assembled pair of the Race Rite heads runs approximately $1,939.

7/17

Holley(270) 782-2800www.holley.com

Aluminum Oval Port 261cc Intake BBC Cylinder Head

Holley gets it done with a pair of aluminum oval port heads that have been CNC-machined. They are made for engines made from 1965 to 1975 with EGR (pn 300-556), and without EGR (pn 300-554). The Holley heads have 261cc intake and 110cc combustion chamber that are designed for low compression pump gas use. These heads come with a 2.19 and 1.88 intake and exhaust valves and stock location exhaust ports. An assembled set of heads will run about $2,200.

8/17

Jegs(800) 345-4545www.jegs.com

"J" Series Cast Aluminum 310cc BBC Cylinder Head

Jegs High Performance not only sells just about any performance part you can think of, it also sells its own performance Rat heads. Jegs "J" series of BBC heads are cast aluminum and CNC-machined for a precise fit. These square port aluminum heads feature 310cc intake runners, as-cast 119cc combustion chambers and raised exhaust ports (.625-inch). Jegs uses longer valves so you will need to check pushrod length. A pair of assembled "J" series heads retails at $1,779 (base price).

9/17

Air Flow Research(877) 892-8844www.airflowresearch.com

Magnum 325cc BBC Cylinder Head

AFR's Magnum heads are available with a variety of upgrades, ranging from intake port sizes starting at 305 cc all the way to 357 cc. The upgrades are almost too numerous to list, so we'll take a look at the as-cast, CNC bowl-blended, aluminum Magnum 325cc intake port head. This particular head comes with the standard 119cc combustion chambers, 2.250 intake valves and 1.880 exhaust valves. Should you desire a fully CNC'd set of heads from AFR, all you have to do is ask. A pair of the 325cc heads usually retails for around $2,485.

10/17

Edelbrock(800) 416-8628www.edelbrock.com

Oval Port Aluminum Performer 290cc BBC Cylinder Head

The Edelbrock Performer series of cylinder heads really needs no introduction. The oval port aluminum Performer heads feature 290cc intake ports and 110cc combustion chambers with 2.19 and 1.88 intake and exhaust valves. The Performer is a great streetable head and retails for about $1,920.

11/17

GM Performance Parts(877) 892-8844www.airflowresearch.com

Oval Port Aluminum 290cc BBC Cylinder Head

GMPP has a pair of great aluminum oval port heads featuring 290cc intake runners and 110cc combustion chambers and 2.250 and 1.880 intake and exhaust valves. The exhaust ports are in the stock location so there's no need to mess around with new headers. Out of the box, an assembled pair of these heads will run about $1,920.

12/17

Trick Flow Specialtieswww.trickflow.com(330) 630-1555

Oval Port Aluminum 280cc BBC Cylinder head

Trick Flow also has a few big-block cylinder heads, but we will focus on its premier budget cylinder head, the oval port aluminum version. It helps build great low- to mid-range horsepower. These heads have 280cc intake runners and 113cc combustion chambers. An assembled set of these heads runs approximately $1,925.

13/17

Powerhouse Engine Components(661) 861-0167www.enginekits.com

Cast Aluminum 320cc BBC Cylinder Head

Powerhouse surprised us with a set of cast aluminum big-block heads that feature 320cc intake runners and 115cc combustion chambers. The intake and exhaust valves measure in at 2.25 and 1.88 respectively. These heads are assembled for hydraulic flat tapped lifters, and upgrades are available, so give them a call. An assembled set from Powerhouse will cost $1199.

Going Back To Last MonthEditor's note: Due to circumstances beyond our control, the following text and photos from part 1 of this story (which dealt with small-block cylinder heads) were left out of the May issue. Here is the conclusion of Head Trip, Part 1, in its entirety. We apologize for the error.

Are you looking for a good set of heads to up the performance factor of your Vortec engine? Summit Performance Vortec cylinder heads have what it takes to get the job done. Featuring wide-open intake runners, efficient combustion chambers, and a high-performance valve job, these heads deliver plenty of power-building airflow. Made from superior iron alloy, these heads come ready-to-run for improved performance straight out of the box.

Dyno-tested on a 383ci engine, Trick Flow's 64cc 23? 195cc aluminum cylinder heads made 460 hp and 451 lb-ft of torque-40 more horsepower and 11 lb-ft more torque than the same engine with GM L98 Corvette heads. The 195 heads are a direct fit, high-performance replacement for most original equipment factory heads, and accept most factory accessories. They feature a choice of 62cc as-cast, or 64cc and 72cc CNC-profiled combustion chambers, 2.02/1.60 stainless steel valves, hardened exhaust valve seats for unleaded gas, and 195cc intake ports with a high-velocity, small cross-section design to promote low-rpm torque without sacrificing higher-rpm horsepower. The heads are available with three spring sizes: 1.250-inch single for cams up to .480-inch lift; 1.470-inch single for cams up to .540-inch lift; and 1.460-inch dual for cams up to .600-inch lift. They come fully assembled with valves, valve springs, locks, retainers, rocker arm studs, and guideplates. The heads are 50-state emissions-legal under CARB E.O. number D-369-4. Cost: approximately $1,249 (assembled).

17/17

Edelbrock(310) 781-2222www.Edelbrock.com

Performer 170cc Aluminum SBC Cylinder heads

The key to any successful engine buildup lies in using parts that work together, and Performer RPM cylinder heads are designed specifically for street-driven cars with moderate compression and pump gas. The high velocity 170cc intake ports produce outstanding throttle response and torque, with enough air flow to produce over 400 hp when used with matching a Performer RPM manifold, cam, and carb. The Performer RPM head #60899 comes fully assembled and ready to run with 2.02/1.60-inch stainless steel valves; valve springs rated up to .575-inch lift; 64cc combustion chambers; 60cc exhaust ports; and straight spark plugs for use with standard exhaust headers. Performer RPM small-block Chevy heads are also available bare, or complete with 70cc combustion chambers and angled spark plugs. Like all Edelbrock heads, they're cast at the Edelbrock Foundry from 356-T6 aluminum and incorporate Heli-Coil inserts in the rocker stud and exhaust bolt holes for strength and durability. Cost: The MSRP is $1,648, but check with your local Edelbrock dealer for more info.

We fire up our hybrid LS3 stroker for more hp. Instead of using rectangular port heads we use the older design cathedral port heads to show that they make great power and are the preferred design for power below 6,000 rpm.